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Ls Dyna Version 971 14: How to Perform Topology Optimization with LS-TaSC



A powerful new feature available in LS-DYNA version 971 is the *SENSOR keyword. To briefly summarize the Keyword Manual description, *SENSOR allows boundary conditions and various model entities to be activated/deactivated based on element, force, and/or node based criteria.


All the input files incorporate the new material (MAT type 159 or MAT_CSCM) to be released in LS-DYNA version 971. The user obtained a beta binaries release of LS-DYNA version 971 for the following platforms/operating systems: SGI IRIX (version 971 release 1490 double precision ), MS-Windows (version 971 release 1612 single precision), and Linux Intel 32 bit architecture (version 971 release 1708 single precision). The SGI IRIX binary crashed with a floating point exception error during the initialization phase of reading an input file. The researchers believe the crash occurred because the SGI binary beta release (1490) might not be as "bug free" as the other binaries.




Ls Dyna Version 971 14




We also have version-specific modules for each version of MPP-DYNA. Each of these modules adds the single and double precision versions ofMPP-DYNA to your PATH as "mpp_s" and "mpp_d", respectively, along with and "l2a_s" and "l2a_d", the single and double precision versions of l2a. Each module also sets up your environment for the latest installed version of the appropriate MPI library. You will not need to load these modules at the command line unless you intend to run one of these programs manually, as qsub-mpp-dyna will load the appropriate module for you automatically.


In our testing with the 3cars, car2car, and neon_refined_revised models from TopCrunch, we've found that the fastest binaries are generally the "pgi-hp" versions, and that the 7600.12.1224 version is the fastest of those. However, newer versions have numerous bugfixes and enhancements. We do not currently recommend the hybrid versions, as they're considerably slower than the pure MPP versions. Versions with "alpha" or "beta" in the name may or may not work.


The qsub wrapper script "qsub-mpp-dyna" simplifies the submission of MPP-DYNA jobs to Torque. The script will automatically write and submit a Torque job script for you. It will also ensure that the job releases its licenses back to the license server.


To use smp version of LS-DYNA on the cluster you need to choose one of the "smp" modules. Switches "--modules" and "--smp" are mutually exclusive. In order to submit your smp job to more than one core you need to specify also number of CPU's in the input file as foolows:


This file will cause the job to be divided into the number of cores you specify; after the decomposition, no further calculations will be performed (assuming the number of cores is > 1). In this case, the decomposition data will be written to the file "decomp_data.pre" (for versions before R4) or "decomp_data.lsda" (for versions R4 and later). Note that the "file" keyword is required, although the manual says it isn't.


Note that the LSTC license server does not accurately keep track of the number of licenses in use on quad-core CPUs for some older versions of MPP-DYNA. Consequently, lstc_qrun and qdyna may report the wrong number of licenses in use.


Creating job scripts, submitting jobs and checking their status can be performed also in graphical mode. Once you log into the cluster using NoMachine or other software you can run qsub-dyna-gui application (with qsub-dyna-gui command).To create a new job script using qsub-dyna-gui you will have to go through the tabs from the left to the right side and input at least required data: input file, LS-DYNA version and number of nodes. Other fields are optional only and for some of them default values will be assigned if not entered by the user.


Purpose: The laminar region of the optic nerve head (ONH), thought to be the site of damage to the retinal ganglion cell axons in glaucoma, is continuously loaded on its anterior and posterior surfaces by dynamic intraocular pressure (IOP) and orbital cerebrospinal fluid pressure (CSFP), respectively. Thus, translaminar pressure (TLP; TLP = IOP-CSFP) has been proposed as a glaucoma risk factor.


CRediT Author Statement: A.K. was responsible for conceptualization, methodology, formal analysis, investigation, and writing of the original draft. R.R. was responsible for conceptualization. S.M.R. was responsible for conceptualization. C.G. was responsible for supervision, writing - review and editing, and funding acquisition. J.C.D. was responsible for conceptualization and experimental design, supervision, writing - review and editing, funding acquisition, and project administration. Approving final version of manuscript was done by all the authors.


The lifting and excavating industry are not as advanced as automotive in the use of modern CAE tools in the early stages of design and development of heavy machinery. There is still a lack of confidence in the integrity of the results from FE simulations and optimisation and this becomes a barrier to the adoption of virtual prototyping for vehicle verification. R&D of Tata Steel has performed tests on two forklift truck overhead guards supplied by a major manufacturer. Based on the international standard for Falling Object Protective Structures (FOPS) as an initial input to the method of testing, the main aim of this study was to generate as much test data as possible to correlate the Finite Element (FE) simulations of two tests - a static and a dynamic test. The static test was developed to deform the overhead guard plastically in a slow controlled manner, so it would be easier to correlate the measured data to FE simulation. A dynamic test is always very difficult to correlate due to the fact that the whole test is over in less than a second and the dynamic response of the structure makes the data extremely noisy. However, this paper demonstrates that paying close attention to all of the input data for an FE model results in a close correlation between the test and the FE simulation even in highly dynamic conditions. 2ff7e9595c


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